


The Biology of Cinnamon and Honey Vanilla

by orphan_account



Category: Big Hero 6 (2014)
Genre: Alpha Tadashi, Anal Fingering, Anal Sex, Biting, Bonding, Dubious Consent, Fluff and Smut, Idiots in Love, Knotting, M/M, Marathon Sex, Mating Cycles/In Heat, Multiple Orgasms, Omega Hiro, Omega Verse, Prostate Massage, Rimming, Self-Lubrication, Sibling Incest, Unhealthy Relationships
Language: English
Status: Completed
Published: 2014-12-08
Updated: 2014-12-08
Packaged: 2018-02-28 15:49:09
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 4,974
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2738147
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: <blockquote class="userstuff">
              <p><em>"It's an old evolutionary tactic for omegas to be physically stronger and more resilient than all other ranks during their heats, in order for them to withstand even the roughest matings and to fend off rutting alphas, and Tadashi, desperately trying to keep himself from going into a rut, is weaker than his brother for the first time in his life."</em><br/> </p><p>Tadashi had always believed that he would be a beta.</p>
            </blockquote>





	The Biology of Cinnamon and Honey Vanilla

**Author's Note:**

> hey look it's the omegaverse fic no one asked for but you're all getting anyway

Before he presented, Tadashi had always believed that he would be a beta.

Certainly, his eldest, most conservative relatives believed this by his consistency, his tendency towards logic. He fit the exact portrait of the beta stereotype: non-aggressive but assertive, highly intelligent, less physically prominent, and wise beyond his years. In their eyes, he was not domineering and aggressive as an alpha, nor sweet and loving as an omega, and certainly not as charismatic as a delta. And while their perceptions on what social ranks truly meant were certainly flawed, Tadashi himself had been quite aware of the actual biology of the matter and how well he fit into such stereotypes.

To him, it was clear in the lack of physiological hints that would occur in other ranks. He'd watched as one by one, his peers showed clear tendencies to shadow biological attributes and statistical trends  of each of their unique ranks: Caitlin had not presented until she was in her late twenties, as most alphas did; physically smaller and weaker than all the rest of his peers, John had presented as an omega at twelve and found his soulmate at sixteen; and Alex, like most deltas, was asexual. Gogo, the same age as Tadashi, had yet to present and felt no stirrings of it, and was most likely to present as an alpha, while Honey and Wasabi had already presented as betas in the past year, and Fred had presented as a delta long before he became friends with anyone in the Nerd Lab.

To Tadashi, it seemed the only possible answer. At twenty-one, around the common age for betas to present, he hadn't presented yet but could feel the stirrings of it in his gut, and like the majority of betas, he was queer (multisexual, to be exact). He was too broad and tall to present as an omega but was smaller than the average delta, and he'd certainly never felt any response to the scent of an omega in heat.

So, upon waking on the eve of his twenty-second birthday, he was startled and disturbed to find the head of his suddenly-much-larger cock swollen and leaking copious amounts of semen all over his sheets.

Of course, Aunt Cass had thrown him a party (“You should be excited, it's your first step into true maturity!”) and Hiro had teased him about his incorrect predictions (“Your nerd skills failed you yet again, nii-chan!”), but his friends had shared his surprise, agreeing that his presentation as an alpha was certainly unexpected.

“I was certain you'd be a beta,” Honey had told him cheerfully. “You'd seemed so sure of it yourself!”

“I thought you'd be a delta before I knew you weren't asexual,” Wasabi had admitted.

“You're small for an alpha,” Gogo informed him, and Fred had snickered in agreement.

Certainly, Tadashi cannot quite find that his status as an alpha has changed much in his life. Of course, he is more than aware now of new limitations, such as how to avoid going into a rut at the scent of a heat and what detergent is most effective to wash his sheets in. He still works at the café part-time, attends all his classes, wears mostly the same clothes, and still coddles Hiro whenever possible (not that he'd admit that to his ototo, of course.) He still works for hours in his lab perfecting Baymax, and spends his Friday nights waiting tables at the cafe and playing Ghibli movies on all the café televisions.

As much as Tadashi is satisfied with his rank, however, he can’t help but wish he'd presented as something different. To bond meant to connect two souls together, was a mark of the strongest relationship one could have, be it out of romantic love or one of deep friendship, although certainly friendship bonds were far easier form and much less complicated. As a beta, or even a delta or omega, he could have bonded romantically with a number of others, had a better chance at looking for someone to spend his life with. As an alpha, however, he could bond platonically, but only once romantically, and if it broke, he would not receive a second chance.

There was only one person Tadashi wanted to spend his life with like that, and that was Hiro.

It wasn't unheard of for blood relatives to bond—it happened on rare accidents, typically as platonic bonds, and while romantic bonds weren't exactly smiled upon, no one tried to break the bond as long as the two were consenting adults. But Hiro was his brother, his ototo who didn't hear Tadashi whisper his name as he stroked himself, thought nothing of all the lingering touches, didn't want his brother the way Tadashi did, and Tadashi knows that Hiro would never want the kind of bond that he ached so deeply for.

It's not until Hiro presents as an omega that everything changes.

* * *

Hiro stares down at his plate, lower lip jutting out in a pout. _It's hot wings,_ he tells himself. _Aunt Cass' hot wings. You_ love _these._ He pokes at one with a finger, but he can't bring himself to pick it up, let alone eat it.

“Hiro? Are you all right?”

The boy looks up from his dinner plate, still frowning, and meets Tadashi's worried gaze. “You haven't eaten anything,” Tadashi continues, scooting his chair closer and placing his palm against his brow. “Are you all right?” His brow furrows and he hums anxiously. “You're warm.”

Hiro tries not to shudder at the touch and sighs, gently brushing away Tadashi's hand. “I'm fine,” he says, rolling his eyes at Tadashi's unconvinced expression. It's just the two of them—Aunt Cass is in New Seoul speaking with investors looking into her café—so there's no one to help hold the full weight of Tadashi's coddling at bay. “Look, I'm just not hungry right now. I'll be fine in a little bit, so just wait, okay?”

Tadashi reaches out and takes Hiro's hand, tugging Hiro to his feet and pulling him close with a disapproving hum. “Come on, you need to lie down for a bit.”

Hiro burns a brilliant pink and opens his mouth to protest, but Tadashi has already turned and is dragging Hiro up the stairs and into their room, pushing the door open and pulling him across their room. He flings back the covers of Hiro's bed and nudges him toward it, and when Hiro refuses, glaring stubbornly at his older brother, he picks him up and dumps him onto his mattress.

“Tadashi, will you stop worrying so much?” Hiro says in exasperation, groaning as his brother pulls the covers up to his chin. He pushes them back down and sits up, eyes narrowed. “I'm sixteen already, you can stop treating me like a child.”

“I worry because you're a reckless little shit and because you're my brother,” Tadashi tells him patiently, pressing Hiro back onto the bed and pushing the covers back up. “Now lie down and take a nap or I will sit on your legs until you do.”

“You do that, and I'll kick you off,” Hiro says grumpily, even though they both know how empty the threat is—besides being a few inches shorter than his brother, Hiro is also ten pounds lighter and physically weaker.

Tadashi smiles and leans forward to press a soft kiss to Hiro's brow, stroking his cheek gently with feather-light fingers before he goes to flick the lights off. Before he leaves, he adds, “I'll check on you in an hour,” and shuts the door, leaving Hiro in the dark.

Hiro can feel where Tadashi touched him, the spots on his brow and cheek tingling. He sighs, shifting to his side and letting his eyes slip shut.

He's always loved his brother, even with his overprotective fussing and hovering, but Hiro had never quite comprehended how much or in what manner, at least until Tadashi presented as an alpha. He's certain his older brother never quite noticed all the ways he had changed, from the way the scent of cinnamon and musk mixed with the clean smell of his aftershave and detergent to the way his shoulders had broadened just slightly and his hair had become a bit thicker. However intelligent Tadashi may be, his tendency to be completely oblivious meant he'd never even consider that he was beautiful enough that people would stop in the street and stare, never see the starstruck gazes or hear how people whispered in admiration after holding even the smallest conversation with him.

Seeing so many captivated people pining away after his newly presented brother had made him annoyed and jealous. How dare they ignore the perfection that was his brother, he’d thought, only to beg for his attention as if only now was he worth their admiration? Even before Tadashi had presented as an alpha, Hiro had spent enough long hours watching his brother work, captivated simply from the way he ran a hand through his hair when upset or chewed on the inside of his cheek when in deep thought. He could spend days talking with Tadashi on any subject, be it robotics or politics, could tell him anything, and Tadashi would understand, even if he didn't always agree. No one understood him the way his brother did, and Hiro liked to think that no one ever would. Hiro loved Tadashi more than anything else in the world, and as Hiro had realized, in more far more ways than just as a brother.

It had gotten worse the past few months, Hiro thinks forlornly, and even more so in the past few weeks. Once upon a time, he would have been content as long as he could be close with his brother, know that he was safe, but Hiro aches now, fingers itching to slide into Tadashi's hair and tug him down, wants to touch him so badly it burns like a physical need. The way Tadashi smiles at him makes Hiro want to launch himself straight into his brothers arms and kiss him until the world ended, melt into his touch and never leave.

The irony of it was that Tadashi loved him just as much. Hiro knows Tadashi would give him the world if that was what he wanted, present him the universe on a silver platter if he asked, and would strong himself up by the ankles as long as it meant Hiro would be safe and happy. _He just can’t love you the way you want him to,_ Hiro thinks miserably.

He falls asleep to these thoughts, and when his brother reenters the room to check on him, he doesn't wake up.

* * *

The next time Hiro wakes, it's nearly six in the morning, and he hurls himself into the bathroom, grips the sides of the toilet, and retches into the bowl. It takes less than thirty seconds for Tadashi appear behind him and murmur gently in his ear, holding the hair back from his face and stroking his back soothingly as he gags and shudders, bile burning his throat until there is nothing left to expel.

He slumps back a half hour later, whimpering slightly, and shivers and pushes at his brother's chest when Tadashi cups his face and cleans around his mouth gently. “M'fine,” he protests faintly, flinching away from the damp washcloth and mumbling incoherently when Tadashi tosses the cloth into the bathtub and scoops him up into his arms.

“Let's get you back to bed.” Tadashi tucks him back in, kissing his forehead. “Oh, Hiro, you're burning up,” he murmurs softly, and Hiro flushes, burying his face in his pillow. “Guess there's no going to school today, then.”

 _“No._ No … I need—” Hiro mumbles. _“Class,_ Tadashi, I need … I can't miss …”

“You have to stay home,” Tadashi admonishes him, tucking him back into bed and pulling the trashcan close to his bedside. “It's okay, Hiro, just go back to sleep, okay?”

Hiro grumbles and squirms, then reaches out and tugs weakly at his brother's shirt. “Get me the work,” he demands, and Tadashi sighs, nuzzling Hiro's cheek.

“I'll go for a little bit and get you notes and homework, but I’m not leaving until you promise to stay home and sleep. Okay?”

Hiro sighs and nods grudgingly before nuzzling closer to him, inhaling deeply, and Tadashi looks down at him in amusement and fondness. He strokes his hair before rising, grabbing several blankets and spreading them over Hiro to keep him warm. His little brother shivers, whimpering before his soft noises slow and he grows silent. Tadashi watches as his breathing steadies, heart twinging oddly in his chest, and goes to get ready for school.

Four hours later, long after Tadashi has left for school and long before Tadashi promised to return, Hiro is burning.

Every inch of his skin prickles, oversensitive. Even the slightest caress of cloth against skin, a wayward breeze, sends electric spikes of pleasure up his spine, and he writhes upon his mattress, gasping and whimpering. His cock twitches and bobs, drooling precum all over his stomach, but it's his hole that aches, fluttering and spasming. Hiro has never felt so empty, never needed to be filled, made complete and whole, and it _hurts._

He only has enough comprehension in him left to understand that he is presenting, obviously as an omega, and knows that this, his first heat, will last at least a week, two without a partner to spend it with. Hiro exhales shakily, hands slipping down to trace the quivering, newly slick pucker, and slides one, two, three fingers in with ease. He sobs as the burning worsens, and jerks his fingers in and out, moaning at the filthy wet squelches; it only takes a single brush to his prostate for him to arch high off the bed with a cry, stripes of cum shooting high and splattering all across his chest and stomach.

Despite his age and already wildly imbalanced hormones, Hiro is unused to coming this quickly, and certainly unfamiliar with this nonexistent refractory period. It's unsurprising—most omegas lack one regardless of their sex organs—but no less frustrating, and Hiro's head falls back as he   begins again.

His fingers seem to have gained a mind of their own—they grind mercilessly against the spongy flesh, and he shoves another finger in, weeping at the lack of relief. There should be a knot there, pressing in all the right places to relieve the heat bit by bit, but the first heat is always the strongest, it’s obviously impossible for him to knot himself, and Hiro can barely stand up straight, let alone find anyone to take pity on him and give him their knot.

It's worse with the faint scent of alpha lingering in the room, traces of his absent brother that only aggravates his heat. Any omega has the unmatched power to bond regardless of rank and break each through sheer willpower, but bonds with alphas are the strongest and are nearly impossible to break, given that alphas only bond once in their lifetime. Hiro wants that connection with Tadashi more than anything, wants the closest thing he can ever have to a promise that lasts a lifetime, and begins to cry for fingers that are not his own, breathing in the sharp, cinnamon scent of _alpha_.

* * *

 It's almost noon in late May—the perfect weather for eating lunch outside and stargazing—and the hydrangeas are beginning to bloom. The streets blur powdery blue, soft violet, pale yellow, and rich pink as he zooms past on his scooter. Usually he stays at school to eat, but Tadashi's been gone too long and Hiro is home all alone, suffering from what looks to Tadashi like a nasty stomach bug.

He parks his scooter in the garage and pulls off his helmet, setting it on the seat and humming in discontent. Even when sick, Hiro still drags himself down to the garage to build and tinker. Many times before, Tadashi has found Hiro feverishly typing away on three computers at once, snot dripping from his nose and swallowed up by an enormous pile of blankets.

 _If he isn't here, he must be throwing up in the bathroom again,_ Tadashi thinks, and hurries inside. “Hiro? I'm home,” he calls, and makes his way up the stairs.

He's halfway up when the scent hits him like a wall, and Tadashi has to cling to the rail for support, inhaling sharply at the sweet, musky scent that spills over every surface and pushes through the cracks in the door. His head immediately goes dizzy, and he chokes at the snarl that bursts from his throat, hand flying up to block his nose.

 _“Gods,”_ he growls, and it's the strongest, loveliest heat he's every smelled, the taste of honey and vanilla with just a hint of mint and ginseng tangible on his tongue. It smells like _Hiro,_ and Tadashi forces himself not to lower his hand and simply _inhale._ He can feel his pupils dilate with lust and moans, low and rumbling.

He makes it to the top of the stairs and has to grab the rail again, this time because the last, quickly dwindling remainder of his sanity is afraid of what will happen if he lets go. More than anything, he knows he needs to flee, to get far, far away from his brother, but he can't bring himself to leave Hiro to go through this alone.

Before he can decide, the door to their room creaks open slowly, and Tadashi bares his teeth and snarls as the scent doubles in strength. Hiro pokes his head out, and Tadashi wants to pick him up and hold him and never let him go at the sight of him. He's bundled himself up in all his blankets, with only his eyes, feet, and a few tufts of hair visible. His eyes are wide and glassy, and he stumbles from the doorway towards Tadashi with a whimper.

He face-plants into Tadashi's chest and looks up at him with desperate eyes, tugging on his shirt. “Nii-tan,” Hiro slurs, half-drunk with arousal, and Tadashi shudders, hands tightly clutching  his little brother's waist. “You were gone so _long …”_

“Hiro,” Tadashi hisses, and his little brother moans, needy and begging. Tadashi can feel Hiro's legs trembling, as if he can barely hold himself up, and Tadashi finds himself shaking with the effort to keep himself from sinking to his knees to taste the sticky fluid steadily leaking down Hiro's bare legs.

He pulls Hiro back into their room and tosses him onto his bed, trying to nudge him under his covers, but Hiro keeps slithering back to Tadashi, rubbing his nose along his neck and purring at his pulse point. Tadashi stills reflexively, and he yelps as he feels Hiro's mouth part and sharp teeth brush his skin.

“Hiro, _no.”_ Tadashi tries to twist out of his little brother's grip, but Hiro keens and flops himself on top of his surprised brother, knocking him back and burbling as he wriggles around on top of him.

It's an old evolutionary tactic for omegas to be physically stronger and more resilient than all other ranks during their heats, in order for them to withstand even the roughest matings and to fend off rutting alphas, and Tadashi, desperately trying to keep himself from going into a rut, is weaker than his brother for the first time in his life.

And Gods, he wants him so _badly._

“Tadashi,” Hiro pleads, one spasming hand flying up to grasp at his brother's wrist. “Haa—I need— _I need—”_

“Hiro,” Tadashi says raggedly, and when his little brother sobs and grinds down against him, he can feel the wet, silk-soft, trembling pucker twitching right above his cock.

He's _soaking._

The last of Tadashi's control snaps, and he flips them over, slamming Hiro face-down against the bed and holding him there with a vicious snarl.

Hiro catches sight of his brother's expression, ravenous with hunger and pupils ringed only by a bright circle of coppery brown, and then he's face down on the bed, his brother breathing harshly in his ear. He squeaks as a hot tongue traces the shell of his ear and plunges into it. Three fingers stroke down his spine and nudge between his cheeks, stretching his hole wide around them as they thrust inside.

“Nnngh—ahn—!” Tadashi finds his prostate within seconds and takes to rubbing and scratching lightly against it. “Tadashi, please— _ah, ple—hyahh_ —ahnng …”

“Mine,” Tadashi purrs, rubbing harder, and his little brother wails, arching desperately into the touch. He rumbles happily, lapping at Hiro's shoulder and moaning. One hand slips below and tightens around Hiro's cock, preventing him from coming, and Hiro gives a displeased whine. “Going to clean you up, slip inside and breed you, give you my knot and fill you with seed—clean you out with my tongue till you cry—”

“Ta—ah—ah, Tadash—” Hiro shudders and gasps, nerves alight, trying to escape the relentless prodding, and Tadashi croons, massaging the nub between three fingers harshly, a slightly sadistic little burble escaping his mouth as he keeps his other hand clamped too-tight around Hiro's cock. “Ahn— _nahhh,_ haa, _haa~”_

“Drink all your sweet little milk from your cock,” Tadashi slurs, “Lick it all up and swallow you down—”

“Nii-tan, please, _let me come,”_ Hiro sobs, and Tadashi gives a pleased moan, flipping Hiro onto his back and sliding down between his legs, swallowing Hiro to the root and pinching his prostate between jerking fingers.

Hiro comes with a cry, arching up into the tight, wet heat of his older brother's mouth, and Tadashi moans at the taste, drinking him down hungrily and mercilessly milking his prick until his little brother stops tugging frantically on his hair and falls limp.

He flips him onto his stomach again and pulls Hiro's hips up as high as they can rest, spreading the soft globes of his arse and pressing wet, sloppy kisses all along the crease. Hiro gasps as Tadashi's tongue, warm and wet, flicks over his hole once, twice, and again. Hiro jerks and squeaks, shuddering as the muscle traces around his rim before plunging in.

 _“Hya—!”_ Tadashi spears him open with his tongue, humming in pleasure at the taste, and clamps his lips around the hole. Hiro realizes only too late what his brother is doing before Tadashi sucks hard against his pucker, drinking in the heat-slick spilling from the hole. “Ta—Tadashi, w-wait, please, w—hha _ahhn,_ yah, _ahh!”_

His brother groans and tightens his grip, trying to keep a frantically sobbing Hiro from escaping the sensation. Hiro's limbs go limp, and Tadashi keeps him propped up, lapping at the honey-vanilla slick and nipping at the spasming rim before he dives in again.

“N-need to—c-come—” Hiro begs. “N-need—ah, _ah_ —Nii-tan, _ple—hhaaah~”_

Tadashi pulls away slowly, licking the slick that soaks his mouth and chin, and takes himself in hand, tracing his little brother's trembling rim with the head of his cock. Hiro makes an unhappy noise as Tadashi hovers, just the tip of his cock rubbing up against the loose, slick little pucker, and arches up in an attempt to get him inside. Tadashi spreads his legs on either side of Hiro's, drinking in the sight with a vicious, predatory delight, and plunges in without warning.

Hiro's eyes shoot wide open, and he bleats as Tadashi pushes in deeper and deeper. He can feel every vein, every crease, could memorize the surface of his brother's cock just from this. It feels perfect: the girth is just wide enough to stretch him obscenely, pressing deep and hot, and Hiro shudders and keens, arching his back and mewling when his brother finally slides in to the root.

Tadashi pauses for a second, panting, and pulls out until the tip of his prick is just barely popping out of the rim before he slams home, grinding the head of his cock right along Hiro's puffy, oversensitive prostate. Hiro gasps and screams, precum exploding from his prick in a constant, thick, drooling mess, legs trembling with the effort of holding himself up.

 _“Mine,”_ Tadashi moans, shoving in deep and gripping Hiro's hips tightly. _“Hiro,_ you're so _tight,”_ he slurs, and slips his thumbs in to join his cock, tugging at his rim and angling himself to ram directly against his little brother's sweet spot. Hiro wails, writhing and frantically pleading, and Tadashi groans as Hiro squeezes around his cock tightly, pressing close and trailing soft, wet kisses up Hiro's neck.

 _“Yours,”_ Hiro sobs, “Yours, yours—ah— _please—”_

Tadashi is relentless, stabbing thrusts hard and fast, pulls out far and plunges in deep only to slam cruelly against Hiro's prostate, and his little brother buries his face in the sheets, stifling his desperate cries, unable to do anything more than _take_ it.

It seems like several long, glorious hours of Tadashi fucking into him, milking one orgasm out of him after the other. The sheets are damp and sticky with slowly cooling cum, and Hiro's skin is littered with angry red bite marks, when his brother's thrust grow erratic and forceful. Hiro can feel his cock quivering inside of him, can feel the head beginning to expand, and clenches down instinctively on it, desperate for it.

 _“Tadashi,”_ Hiro begs, and Tadashi bites down on his neck _hard_ as he bottoms out, knot expanding right over his little brother's prostate and spilling hot and thick inside of him, trapped deep by the head of his cock. A sharp, gasping cry flies from Hiro's throat, and he paints the sheets below him for the ninth time, going limp with relief and satisfaction.

It's impossible to impregnate an omega in their first heat, but Hiro can feel something warm and solid settle in his chest—a bond—before he passes out from exhaustion, his heat still thrumming in his veins.

* * *

 He wakes with a start to find himself bundled up in countless blankets and fresh sheets. The sky has faded to a soft, pastel sunset with the pinpricks of distant stars just beginning to scatter behind the clouds, complementing the sound of a mourning dove warbling oddly somewhere outside his window.

His alpha is sitting on the floor by his bed, staring forlornly at the clock on the far wall in silence. A washcloth lies on the floor beside him, and Hiro runs his fingers absently along the clean, dry skin of his thighs. Hiro blushes as he sees the scattered, bruising marks littering Tadashi's skin; he's distinctly sure that Tadashi was the one who did the most rough handling, so to see these that he himself had made so unconsciously is more than a little daunting.

For a moment, the two say nothing, and then Hiro crawls to the side of the bed, touching his brother's shoulder tentatively. “Nii-chan?”

Tadashi doesn't move, but closes his eyes, exhaling shakily. “Hiro, I'm so sorry.”

“Tadashi?” A nasty pit begins to form in Hiro's stomach, and he swallows against the bile rising in his throat. “I don't understand.”

His brother shakes his head, shoulders bowing as he puts his head in his hands. “I didn't mean for any of this to happen. Hiro—I swear, I promise I'll do everything to make this okay—”

“You don't … want me?” Hiro's voice cracks, and Tadashi turns to look at him in surprise. “You don't … want to, to k-keep our bond?”

“Hiro?”

The boy closes his eyes, trying to calm himself down. Of all things, this— _this_ is worse than anything he had imagined, worse than watching in silence as Tadashi fell in love, because at least then Tadashi would not have intentionally rejected him as he was now. He would not have ruined things for his brother, taken away his one chance at bonding with someone he wanted to share a life with.

“It's okay,” he says finally, trying to keep his voice from trembling and knowing he was failing miserably. “I understand, a-and Tadashi, I didn't mean to—to take anything away from you.” Hiro looks down at his hands, interlocking his fingers. “Now … now you can't … ever bond again, I mean, I think you can’t, not that romantic love needs to be sexual, I just—maybe not platonic—look, I'm really sorry, I just—I-I wanted—” He squeezes his eyes shut. “I wanted _you—”_

Large, warm hands slide around his waist, and Hiro squeaks. They tug him forward off the bed, onto Tadashi’s lap, and into one bone-deep kiss, and Hiro throws his arms around his brother’s neck, kissing him back as the balloon in his chest swells almost to breaking point. Hiro feels Tadashi’s mouth curve upwards in a smile, and he slides his hands through Tadashi’s hair, soft noises spilling from his throat.

“For a child prodigy, you’re a bit slow on the uptake,” Tadashi teases him when he pulls away, and Hiro makes a face at him, burying his face in his brother’s shoulder.

“I’m not the one who assumed his brother had no feelings for him whatsoever after he fucked him into a mattress.”

Tadashi’s cheeks tinge with pink, and he flicks Hiro on the side of the head. “Language,” he scolds, and Hiro rolls his eyes and laughs.

“You know,” Hiro says hopefully, wriggling slightly, “Since I just presented and all, I’m technically still in heat for the next week or so.”

Tadashi opens his mouth, probably to say something along the lines of, “I literally just knotted you, you little shit, your heat isn’t going to come back in full force for at least twelve hours”, but that is an argument for another time, and Hiro is already tugging him back onto the bed.

 

**Author's Note:**

> and then tadashi becomes addicted to the taste of hiro's omega-slick and eats him out whenever he gets the urge (which becomes increasingly inconvenient) and eventually hiro and the others have to have an intervention and send tadashi to alphas anonymous because apparently this problem is not uncommon


End file.
